The goal of this project is to determine the role of two genomic regions and two categories of non-genetic factors in RA onset and disease expression. Disease expression will be defined in terms of the presence of bone erosions and the development of extra-articular manifestations. The GCRC will obtain blood samples for RF testing at the UCSF Clinical lab and to obtain radiographs of the hands and wrists. During the visit, patients will complete enrollment by providing buccal smear samples and completion of questionnaire.